 /* 添加样式，使弹窗居中显示 */
 #difficulty-sellect-popup {
  width: 300px;
  height: 300px;
  display: none;
  position: fixed;
  top: 35%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: #fff;
  border: 1px solid #ccc;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
  z-index: 999;
}

#difficulty-sellect-popup .layout .content{
  height: 200px;
}

.content-item{
  margin: 10px;
  width: 250px;
}

.content-item-tip{
  font-size: 12px;
}
.content-item:nth-child(1) .content-item-tip,
.content-item:nth-child(2) .content-item-tip{
  color: green;
}

.content-item:nth-child(3) .content-item-tip{
  color: red;
}

input{
  width: 150px;
}
